/**
 * Copyright (c) 2015-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

#import "RCTImageEditingManager.h"

#import <AppKit/AppKit.h>

#import <React/RCTConvert.h>
#import <React/RCTLog.h>
#import <React/RCTUtils.h>
#import <React/UIImageUtils.h>

#import "RCTImageLoader.h"
#import "RCTImageStoreManager.h"
#import "RCTImageUtils.h"

@implementation RCTImageEditingManager

RCT_EXPORT_MODULE()

@synthesize bridge = _bridge;

/**
 * Crops an image and adds the result to the image store.
 *
 * @param imageRequest An image URL
 * @param cropData Dictionary with `offset`, `size` and `displaySize`.
 *        `offset` and `size` are relative to the full-resolution image size.
 *        `displaySize` is an optimization - if specified, the image will
 *        be scaled down to `displaySize` rather than `size`.
 *        All units are in px (not points).
 */

//RCT_EXPORT_METHOD(cropImage:(NSString *)imageTag
//                  cropData:(NSDictionary *)cropData
//                  successCallback:(RCTResponseSenderBlock)successCallback
//                  errorCallback:(RCTResponseErrorBlock)errorCallback)
//{
//  NSDictionary *offset = cropData[@"offset"];
//  NSDictionary *size = cropData[@"size"];
//  NSDictionary *displaySize = cropData[@"displaySize"];
//  NSString *resizeMode = cropData[@"resizeMode"] ?: @"contain";
//
//  if (!offset[@"x"] || !offset[@"y"] || !size[@"width"] || !size[@"height"]) {
//    NSString *errorMessage = [NSString stringWithFormat:@"Invalid cropData: %@", cropData];
//    RCTLogError(@"%@", errorMessage);
//    errorCallback(RCTErrorWithMessage(errorMessage));
//    return;
//  }
//
//  [_bridge.imageLoader loadImageWithTag:imageTag callback:^(NSError *error, UIImage *image) {
//    if (error) {
//      errorCallback(error);
//      return;
//    }
//    CGRect rect = (CGRect){
//      [RCTConvert CGPoint:offset],
//      [RCTConvert CGSize:size]
//    };
//
//    // Crop image
//    CGRect rectToDrawIn = {{-rect.origin.x, -rect.origin.y}, image.size};
//    UIGraphicsBeginImageContextWithOptions(rect.size, !RCTImageHasAlpha(image.CGImage), image.scale);
//    [image drawInRect:rectToDrawIn];
//    UIImage *croppedImage = UIGraphicsGetImageFromCurrentImageContext();
//    UIGraphicsEndImageContext();
//
//    if (displaySize && displaySize[@"width"] && displaySize[@"height"]) {
//      CGSize targetSize = [RCTConvert CGSize:displaySize];
//      croppedImage = [self scaleImage:croppedImage targetSize:targetSize resizeMode:resizeMode];
//    }
//
//    [_bridge.imageStoreManager storeImage:croppedImage withBlock:^(NSString *croppedImageTag) {
//      if (!croppedImageTag) {
//        NSString *errorMessage = @"Error storing cropped image in RCTImageStoreManager";
//        RCTLogWarn(@"%@", errorMessage);
//        errorCallback(RCTErrorWithMessage(errorMessage));
//        return;
//      }
//      successCallback(@[croppedImageTag]);
//    }];
//  }];
//}

- (NSImage *)scaleImage:(NSImage *)image targetSize:(CGSize)targetSize resizeMode:(NSString *)resizeMode
{
  if (CGSizeEqualToSize(image.size, targetSize)) {
    return image;
  }

  CGFloat imageRatio = image.size.width / image.size.height;
  CGFloat targetRatio = targetSize.width / targetSize.height;

  CGFloat newWidth = targetSize.width;
  CGFloat newHeight = targetSize.height;

  // contain vs cover
  // http://blog.vjeux.com/2013/image/css-container-and-cover.html
  if ([resizeMode isEqualToString:@"contain"]) {
    if (imageRatio <= targetRatio) {
      newWidth = targetSize.height * imageRatio;
      newHeight = targetSize.height;
    } else {
      newWidth = targetSize.width;
      newHeight = targetSize.width / imageRatio;
    }
  } else if ([resizeMode isEqualToString:@"cover"]) {
    if (imageRatio <= targetRatio) {
      newWidth = targetSize.width;
      newHeight = targetSize.width / imageRatio;
    } else {
      newWidth = targetSize.height * imageRatio;
      newHeight = targetSize.height;
    }
  } // else assume we're stretching the image

  // prevent upscaling
  newWidth = MIN(newWidth, image.size.width);
  newHeight = MIN(newHeight, image.size.height);

  // perform the scaling @1x because targetSize is in actual pixel width/height
  UIGraphicsBeginImageContextWithOptions(targetSize, NO, 1.0f);
  [image drawInRect:CGRectMake(0.f, 0.f, newWidth, newHeight)];
  NSImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();

  return scaledImage;
}

@end
